The use of RFID tags to identify and track cargo is already common, and expected to grow. Inevitably, many such tags will be used on air freight shipments. Therefore, the effects of such RFID tags on common avionics is an issue of concern to owners, operators, regulators and the traveling public. A recent study by NASA Langley Research Center identified a particular RFID device having a relatively high level of emissions in the 328.6-335.4 MHz band associated with the Instrument Landing System Glide Slope function.This paper summarizes a small NASAsupported study performed by the technical staff of the Honeywell Aerospace Advanced Technology organization to estimate the effects of the measured emission levels and signal structure on the Glide Slope guidance function. The paper includes a derivation of the guidance error variance, a model for accommodating RFID duty cycle, and application of the simple analysis recommended by RTCA/DO-294B. The conclusion is that, under likely operating conditions, low duty cycle RFID tags such as the specific family identified by NASA should have no meaningful effect on GS operation. Extrapolations to other narrowband receiver systems reach similar conclusions.

The use of intentionally transmitting portable electronic devices, such as cell phones, WiFi devices, Bluetooth headsets, etc., is widespread and growing. RTCA Special Committee 202 has been considering guidelines for the use of such devices on aircraft. A key element of the assessment of such devices is the quantitative expression of the effect of the intentional and unintentional (spurious) emissions of such devices on the communications, navigation and surveillance radios used on the aircraft. These radios were generally not designed to accommodate interference from consumer devices operated on-board the aircraft. This paper develops the performance equations necessary to evaluate the effects of emissions from such intentionally transmitting devices to the LBand Distance Measuring Equipment, and uses these equations to recommend appropriate susceptibility thresholds. The resultant thresholds will be incorporated into the recommendations of SC-202, as documented in a modification of RTCA/DO-294B.

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In coherent UWB receivers, creating a template to exactly match the received signal is usually difficult and costly. If a simplified template is employed, the receiver's performance will degrade due to the unmatched template. This paper proposes a pulse shaping optimizer with genetic algorithms to maximize the signalto-noise ratio (SNR) of the received signals and therefore reduce the performance degradation for arbitrary receiving template in UWB receiver.

<p class="MsoNormal" style="text-align: left; margin: 0cm 0cm 0pt; layout-grid-mode: char;" align="left"><span class="text"><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;">This paper studies the in-band interference of time-hopping spread spectrum (TH-SS) ultra-wideband (UWB) signals to narrowband receivers. Based on the analysis of general power spectral density (PSD) of TH-SS UWB signal, the interference of UWB signal is partitioned into two parts: (1) additive white Gaussian noise interference, and (2) jamming tone interference. Following this framework, a novel analytical symbol error rate (SER) evaluation method for binary phase-shift keying (BPSK) and M-ary phase-shift keying (MPSK) signals subject to UWB interferences is proposed and corresponding simulation results are demonstrated. It is shown that as the number of in-band jamming tones increases, the UWB interference effect tends to be closer to the effect of the equivalent Gaussian noise. When there is only one UWB tone interferer within the narrowband receiver bandwidth, and when the signal-to-interference-and-noise ratio is higher than a certain value, the narrowband symbol error rate decreases as the relative tone power portion in the overallinterference and noise power increases.</span></span><span style="font-family: ";Arial";,";sans-serif";; font-size: 9pt;"></span></p>